In chess, a tactic refers to a sequence of moves which limits the opponent's options and may result in tangible gain. Tactics are usually contrasted with strategy, in which advantages take longer to be realized, and the opponent is less constrained in responding.

The fundamental building blocks of tactics are move sequences in which the opponent is unable to respond to all threats, so the first player realizes an advantage. This includes forks, skewers, batteries, discovered attacks, undermining, overloading, deflection, pins and interference.

Often tactics of several types are conjoined in a combination.

A piece is said to attack (or threaten) an opponent's piece if, in the next move, it could capture that piece. A piece is said to defend (or protect) a piece of the defender's color if, in case the defended piece were taken by the opponent, the defender could recapture right away. Attacking a piece usually, but not always (see sacrifice), forces the opponent to respond if the attacked piece is undefended, or if the attacking piece is of lower value than the attacked one.

Jennifer Shahade (born December 31, 1980 in Philadelphia, Pennsylvania) is an American chess player and writer. She is a two-time American women's chess champion and, as of October 2007, has a FIDE rating of 2322. She has the FIDE title of Woman Grandmaster. Jennifer is the author of the book Chess Bitch. She also writes for the magazine Chess Life and is the daughter of FIDE Master Mike Shahade and Drexel University chemistry professor and author Sally Solomon, and the sister of International Master Greg Shahade.

In 1998, she became the first (and so far only) female to win the U.S. Junior Open. In 2002, she won the U.S. Women's Chess Championship in Seattle, Washington. The following year, although she did not repeat as U.S. Women's Champion, she did well enough to earn her second of three required International Master norms. In 2004, she returned to the top spot among U.S. women chess players by winning the U.S. Women's Championship that year in a seven-player invitational round-robin tournament.

Varuzhan Akobian (born November 19, 1983 in Yerevan, Armenia) is an Armenian-American Grandmaster of chess, originally from Armenia, who now resides in Los Angeles. He played on the bronze-medal-winning USA team in the 2006 and 2008 Chess Olympiads.

Akobian became an International Master at age 16. In 2001, he moved to the United States and one week after his 20th birthday in November 2003, earned the title of Grandmaster.

He won the World Open tournament in Philadelphia on three separate occasions; he shared first place in 2002 and won it outright in 2004 and 2007. In 2006 he tied for first in the San Marino tournament with a performance rating of 2796. In 2007 he tied for 1st–8th with Hikaru Nakamura, Alexander Shabalov, Darmen Sadvakasov, Zviad Izoria, Victor Mikhalevski, Magesh Chandran Panchanathan and Justin Sarkar in the Miami Open and came equal first in the American Continental Championship in Cali, Colombia. This qualified him for the Chess World Cup 2007, where he was eliminated in the first round. He also took part in the Chess World Cup 2009 and was knocked out by Ruslan Ponomariov in the second round.

Edward Lasker (December 3, 1885 – March 25, 1981) was a leading German-American chess and Go player. He was awarded the title of International Master of chess by FIDE. Lasker was an engineer by profession, and an author.

Edward (then Eduard) Lasker was born in Kempen (Kępno), Province of Posen (Greater Poland), Prussia, German Empire, (present Poland). He studied in Breslau (Wrocław) and in Charlottenburg (now part of Berlin). Before World War I he moved first to London, England, and then, in 1914 shortly after the outbreak of war, to America, the birthplace of his mother. He found a job in Chicago. When America entered the war in 1917, he was sent enlistment papers, but with the right of exemption as a German. He waived his right to exemption, which he said would make his American citizenship be granted more quickly; however, the war was over before he was called up to military service.

Lasker earned undergraduate degrees at the Technical College of Charlottenburg in Mechanical and Electrical Engineering. In 1921–23, he invented a mechanical breast pump, which saved many premature infants' lives and made Lasker a lot of money, although it caused his friends to refer to him facetiously as "the chest player".

Susan Polgar (born April 19, 1969, as Polgár Zsuzsanna and often known as Zsuzsa Polgár) is a Hungarian-American chess Grandmaster. She is an Olympic chess champion, a chess teacher, coach, writer and promoter and the head of the Susan Polgar Institute for Chess Excellence (SPICE) at Texas Tech University as well as the coach for the 2011 National Championship college chess team. She is the oldest of the famous "Polgár sisters": Zsuzsa, Zsófia, and Judit. Susan is perhaps most famous for being a child prodigy at chess, for being the first female to earn the Grandmaster title through tournament play, and for breaking a number of gender barriers in chess.

On the July 1984 FIDE Rating List, at the age of 15, she became the top ranked woman player in the world, and remained ranked in the top three for the next 23 years. She was also the first woman in history to break the gender barrier by qualifying for the 1986 "Men's" World Championship. She was the Women's World Chess Champion from 1996 to 1999. In October 2005 Polgar had an Elo rating of 2577, making her the second-ranked woman in the world at the time, after her sister Judit Polgár. Polgar went on to win ten Olympic medals (5 Gold, 4 Silver and 1 Bronze) and four Women's World Championships. She has not played in official competition since 2006.